Cooking device with a catalyst

ABSTRACT

A cooking device has a cooking chamber, a ventilation device in the form of a ventilating fan wheel or the like and a heating device plus a catalyst. Air from the cooking chamber, including greasy vapors, odor particles, and/or hydrocarbons, can be directed in a finely-atomized form onto the catalyst by the ventilation device. The catalyst purifies the air directed thereon and releases energy in the form of heat during purification, which heat can be distributed inside the cooking chamber by the ventilation device.

BACKGROUND OF THE INVENTION

The invention is directed to a cooking device having a cooking chamber,a blower chamber, an air baffle, a ventilation means or device in theform of an aerator wheel or the like, a heating device and a catalystmeans. The air baffle comprises at least one admission and dischargeopening for air circulation between the cooling chamber and the blowerchamber. Air, including fat vapors, odor particles and/or hydrocarbons,from the cooking chamber and finely atomized by the ventilation devicecan be conducted from the cooking chamber onto the catalyst means. Thecatalyst means cleans the air directed onto it while outputting energy,and the cleaned air and/or the energy released in the cleaning in theform of heat can be distributed into the cooking chamber via theventilation device. The catalyst of the catalyst means is arrangedessentially concentrically around the heating device, and the heatingdevice is arranged essentially concentrically around the ventilationdevice.

DE 41 39 904 A1 discloses a backing or broiling oven with an oven mufflewherein a motor-driven blower wheel is arranged neighboring the backwall. Concentric therewith, a heating element and a catalyst that istransmissive for the air conveyed by the blower wheel, are arrangedsuccessively in a flow direction. In order to achieve a high catalyticeffect, the catalyst is fashioned in the form of a sponge whoseeffective surface is coated with a catalytically active coat.

The article, “Heiβe Platten”, in Elektromarkt No. 3, March 1196, pages16 through 22, discloses the employment of a catalyst for convertingodors and fat vapors that arise when baking and frying into pure, humidair. In contrast to other cleaning systems, neither additional time norpower is thereby required, since the catalyst also generates conversionheat that can also be employed for heating the foodstuff to be cooked.

DE 35 16 847 A1 discloses an electric range with a catalyst wherein anexternally heated catalyst is introduced into a fume exhaust opening.

An apparatus for separating solid and/or liquid particles from a gasvolume having at least one impact surface disclosed by DE 42 06 846 C2.

DE 198 24 172 discloses a cooking device with an energy store and energyremoval system that is connected to a measurement and control systemalready present in a traditional cooking device, so that, on the onehand, heating capacity can be reduced and, on the other hand, waste heatcan be used. An energy store can be charged during cooking pauses, whichalways arise in a batched mode or are caused due to the cookingexecution, and/or in a cooking phase wherein a cooking process requireslittle or no energy with a potentially additional heater controlled viathe measurement and control system. Heat energy is stored in the energystore according to a priority hierarchy for assuring an undisturbedimplementation of a cooking process, or by the heat from exhaust airemerging from the cooking chamber or, respectively, excess steam thatemerges, and energy is taken from the energy store during high-energycooking phases wherein the cooking process requires a great deal ofenergy, more than the heater, which is installed for heating thefoodstuffs to be cooked, can deliver.

In particular, EP 0 772 514 B1 discloses self-cleaning cooking surfacesthat can be realized by artificial implementation of a microscopicsurface structure, as known for the lotus blossom, in hydrophobicpolymers which are materials rendered durably hydrophobic.

SUMMARY OF THE INVENTION

An object of the present invention is to improve the cooking device ofthe species to the effect that the disadvantages of the Prior Art areovercome, particularly that coarse dirt, fat splatters and/or the likecan be intercepted and does not or, respectively, do not impinge theheating device, so that the heating device is treated with care.

This object is inventively achieved by an impact surface around whichthe heating device is arranged essentially concentrically, whereby theheating device is arranged at least partially in the flow shadow of theimpact surface.

It can thereby be provided according to the invention that the catalystis fashioned in the form of a plurality of catalyst elements attached toa catalyst housing.

One embodiment of the invention is characterized by an air deliveryconduit via which fresh air can be introduced in a controlled fashion,particularly to stimulate an oxidation of fats, odor particles and/orhydrocarbons.

It is also inventively proposed that the impact surface is arranged inthe back third of the cooking chamber which is in the exhaust direction.

It is also inventively provided that the impact surface is fashioned inthe form of a separator ring for separating solid and/or liquidparticles from a gas volume.

Preferably, the heating device is fashioned in the form of at least one,preferably two, annular heating members.

Further, an energy store system and/or energy removal system withcatalyst properties is inventively proposed.

It is also inventively provided that the cooking chamber, the energystore system and/or energy removal system and/or the heating device isor, respectively, are equipped and/or coated with a catalyst, at leastin regions.

One development of the invention is that the catalyst comprises asurface with a surface structure in dimensions of up to a maximum of 500μm and is self-cleaning.

It can be inventively provided that the catalyst comprises aluminumoxide and/or platinum.

The invention is thus based on the surprising perception that, due tothe specific arrangement of the impact surface such that the heatingdevice is at least partially arranged in the flow shadow of the impactsurface, this heating device can be protected against wear due to thedeposit of dirt, fat and/or the like, since the impact surfaceintercepts such dirt, fat splatters and/or the like. Moreover, the flowthat is, so to speak, precleaned via the impact surface can bedesignationally directed onto the catalyst for enhancing its efficiency.

Inventively, the catalyst can thereby be utilized in the form ofindividual, separate catalyst elements and/or, on the other hand, as apartial coating of the cooking chamber and/or of an energy store systemand/or energy removal system.

Moreover, the catalyst itself can be inventively fashioned such that thesurface structure thereof repels dirt.

Additional features and advantages of the invention derive from thefollowing description, wherein an exemplary embodiment of the inventionis described in detail on the basis of schematic drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial longitudinal section through the inventive cookingdevice; and

FIG. 2 is a cross-sectional view of the inventive cooking device of FIG.1.

DESCRIPTION OF THE PREFERRED EMBODIMENT

As can be derived from FIGS. 1 and 2, an inventive cooking device 1comprises, in particular, a cooking chamber 2 that is separated from ablower chamber 4 by an air baffle 3. The air baffle 3 thereby comprisesat least one admission and discharge opening (not shown) for aircirculation between the cooking chamber 2 and the blower chamber 4.

A fan wheel 10, two heating members 11, 12, a plurality of catalystelements 14 attached to a catalyst housing 13 and an impact surface forthe separation of solid and/or liquid particles in the form of aseparator ring 15 are arranged in the blower chamber 4. An inner heatingmember 11 is thereby arranged concentric with the fan wheel 10, an outerheating member 12 is arranged concentric with the inner at heatingmember 11, the separator ring 15 is arranged concentric with the outerheating member 12, and the catalyst elements 14 are arranged concentricwith the separator ring 15.

When, for example, chickens are cooked in the cooking chamber 2, then apronounced formation of odors and production off at vapors occur withinthe cooking chamber 2. The fan wheel 10 then sees to it that the odorparticles and fats are conducted from the cooking chamber 2 into theblower chamber 4 and onto the catalyst elements 14 therein in order tothus enable a conversion of the odor particles and the fats into pure,damp air that can then be resupplied to the cooking chamber 2. As aresult of the specific arrangement of the impact surface of theseparator ring and of the heating device 11, 12 in the flow shadow ofthe impact surface, air can be directed in a highly directed fashiononto the catalyst elements 14, so that, in particular, a contaminationof the heating device 11, 12 can be avoided.

When cleaning the cooking chamber atmosphere with the catalyst elements,moreover, energy is released that, for example, can be utilized for afurther, designational heating of the cooking chamber 2. The inventivecooking device 1, thus, makes it possible to dispose of fats and otherhydrocarbons that arise during a cooking process with an energy gain.Since the energy content of animal fats lies, for example, on the orderof magnitude of 1 kWh per 100 g, a cost-beneficial and energy-saving aircleaning can be obtained with the inventive structure without, inparticular, contamination of the heating device.

Both individually as well as in arbitrary combination, the features ofthe invention disclosed in the above description, in the claims as wellas in the drawings can be critical for realizing the various embodimentsof the invention.

We claim:
 1. A cooking device comprising a cooking chamber separatedfrom a blower chamber by an air baffle, ventilation means located in theblower chamber for circulating air between the cooking chamber and theblower chamber, an impact surface being arranged concentrically to theventilation means in the blower chamber, a heating device being arrangedconcentrically with the impact surface in a flow shadow of the impactsurface, catalyst means being disposed in the blower chamberconcentrically around the heating device, said ventilation means drawingair including fat vapors, odor particles and/or hydrocarbons from thecooking chamber and directing them in a finely-atomized form onto thecatalyst means, said catalyst means cleaning the air directed onto itwhile outputting energy, said ventilation means taking air cleaned bythe catalyst means and heat energy released during cleaning anddistributing it to the cooking chamber.
 2. A cooking device according toclaim 1, wherein the catalyst means is fashioned in the form of aplurality of catalyst elements attached to a catalyst housingconcentrically surrounding the heating device and impact surface.
 3. Acooking device according to claim 1, which includes air deliveryconduits via which fresh air can be introduced in a controlled fashionto stimulate oxidation of fats, odor particles and hydrocarbons.
 4. Acooking device according to claim 1, wherein the impact surface isarranged in a back region of the blower chamber in the exhaustdirection.
 5. A cooking device according to claim 1, wherein the impactsurface is fashioned in the form of a separator ring for separatingsolid and liquid particles from a gas volume.
 6. A cooking deviceaccording to claim 1, wherein the heating device is fashioned in theform of at least two preferably annular heating members.
 7. A cookingdevice according to claim 1, which includes an energy store system andan energy removal system with catalytic properties.
 8. A cooking deviceaccording to claim 7, wherein at least one of the cooking chamber, theenergy store system, the energy removal system and the heating devicehas at least regions provided with a catalyst.
 9. A cooking deviceaccording to claim 1, wherein the catalyst of the catalyst meanscomprises a surface with a surface structure in dimensions of up to amaximum of 500 μm and the catalyst is self-cleaning.
 10. A cookingdevice according to claim 1, wherein the catalyst is selected fromaluminum oxide, platinum and a combination of aluminum oxide andplatinum.
 11. A cooking device according to claim 1, wherein at leastone of the cooking chamber and the heating device has a region providedwith a catalyst material of the catalyst means.